WKB.loads() fails about geomet HOT 3 CLOSED

Hey @dave-nm, I think there's an error in the input.

0101000020e61000003cdba337dcc351c06d37c1374d374840 does not contain a valid geometry type. (See https://github.com/geomet/geomet/blob/master/wkb_detail.md#point).

I think the problem is that you're missing a byte from the type field:

• the first byte (2 hex chars) is the endianness --> 01
• the next 4 bytes are the geometry type --> 01000020, which is not a valid geometry type (at least none that I'm aware of)
• the rest should be 8 byte chunks, each chunk containing a coordinate value

The first (working) example should convert to {'type': 'Point', 'coordinates': [-71.060316, 48.432044]}, but I don't understand what the other geometry is supposed to be. Can you please clarify?

from geomet.

@dave-nm Ah, I see what it is. The SRID is encoded in there; that's why.

I figured this out by playing with postgis:

postgres=# SELECT ST_GeomFromEWKT('POINT(-71.060316 48.432044)');
              st_geomfromewkt               
--------------------------------------------
 01010000003CDBA337DCC351C06D37C1374D374840
(1 row)

postgres=# SELECT ST_GeomFromEWKT('SRID=4326;POINT(-71.060316 48.432044)');
                  st_geomfromewkt                   
----------------------------------------------------
 0101000020E61000003CDBA337DCC351C06D37C1374D374840
(1 row)

Let me find the documentation on that encoding. This seems to be a PostGIS-specific thing (https://gis.stackexchange.com/questions/143230/i-cant-understand-this-ewkb-type-mask) but I see no reason to not support it.

from geomet.

Closing this issue, moving it to #31 (since it more precisely characterizes the issue/feature).

from geomet.